Opera mini allows few sites for Javascript to run on its client in extreme mode?

When data savings mode extreme is on, Opera mini doesn't allow Javascript to run on the client, and reloads the page to execute it on its server. However I see an exception with few website still able to run the script on the client, how is that possible. Example is the amazon.com, I could see the search, and many other javascript features works without page reloading, how does it work?

There has many website where needs javascript running. But Opera Mini Server paused all JavaScript. It would be great if there has an option to Enable/Disable javascript.
& also it would be good if there has 3 different browsing mode like Opera Mini for IOS. Because currently Opera Mini Android has only 2 mode:- *Extreme & High (Turbo)

It is a configuration set by the Opera Mini servers and you have no option to configure it by yourself. Why would you want it?

As a developer myself I agree with what Opera Mini is achieving with the extreme mode. However, website I am working on needs this to be done, as we noticed there are quite a few websites which have got this configuration already. It would be grateful if you could help me with the pointer who/how to be contacted for the configuration to be set for a website. So I can pass this to people above me in organizational structure to get this done.